First quantum-resistant Bitcoin transaction successfully executed, StarkWare says

StarkWare researcher Avihu Levy has successfully tested an experimental quantum-resistant Bitcoin transaction on the mainnet, marking the first of its kind. The transaction, confirmed in block 964,199, spent a 10,000-satoshi output protected by StarkWare's Quantum Safe Bitcoin (QSB) scheme. The transaction was mined by the MARA Pool after being submitted through their Slipstream service.

QSB combines hash-based one-time signatures with computational searches to bind an authorization to a specific transaction, preventing forgery even if a quantum computer breaks Bitcoin's elliptic-curve cryptography. While the test demonstrates that existing Bitcoin consensus rules can accommodate quantum-resistant spending without a protocol change, the process cost up to $200 and required direct miner submission, making it nonstandard and requiring manual propagation by ordinary nodes.

StarkWare CEO Eli Ben-Sasson stated that a soft fork should occur to address the issue, while QSB serves as a safety net until protocol-level protections are developed.